Abrasion resistant cellulosic fabrics containing graft polymerized diethylphosphatoethylmethacrylate and/or diethylphosphato-ethyl acrylate

ABSTRACT

The abrasion resistance of cellulose and cellulose containing fabrics such as cotton and rayon is improved by graft copolymerizing diethylphosphatoethylmethacrylate and/or diethylphosphatoethylacrylate onto the cellulosic substrate.

United States Patent Brickman et a1.

ABRASION RESISTANT CELLULOSIC FABRICS CONTAINING GRAFI POLYMERIZED DIETHYLPHOSPHATOETHYLMETHACRY- LATE AND/OR DIETHYLPHOSPHATO-ETHYL ACRYLATE Inventors: W. James Brickman, Philadelphia;

Robert W. Faessinger, Media, both of Pa.

Assignees Scott Paper Company, Philadelphia,

Filed: Oct. 2, 1974 Appl. No.: 511,176

US. Cl 260/174 GC; 8/116 R; 8/116 P; 8/194; 8/D1G. 18; 117/1395 A Int. Cl. ..C08L l/02; DO6M 13/32; DO6M 13/44 Field of Search. 260/17.4 GC; 8/116 R, 116 P, 8/194, D16. l8

[ Dec. 9, 1975 Primary Examiner-Melvin Goldstein Assistant Examiner-Edward Woodberry Attorney, Agent, or Firm-Nicholas J. DeBenedictis; John W. Kane, Jr.

[57] ABSTRACT The abrasion resistance of cellulose and cellulose containing fabrics such as cotton and rayon is improved by graft copolymerizing diethylphosphatoethylmethacrylate and/or diethylphosphatoethylacrylate onto the cellulosic substrate.

8 Claims, N0 Drawings ABRASION RESISTANT CELLULOSIC FABRICS CONTAINING GRAFT POLYMERIZED DIETI-IYLPHOSPHATOETIIYLMETIIACRYLATE AND/OR DIETHYLPI-IOSPHATO-ETHYL ACRYLATE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improving the abrasion resistance of cellulose fabrics and cellulose-containing fabrics such as cotton, rayon and cotton-synthetic blends. This invention also relates to imparting durable flame retardant characteristics to such fabrics.

2. Description of the Prior Art The graft copolymerization of cellulosic fabrics usually reduces the abrasion resistance and strength of the grafted substrate and this reduction becomes more pronounced as the quantity of polymer grafted onto the fabric is increased. The graft copolymerization of cellulosic fabrics with conventional fire retardant monomers such as vinylidene chloride, allyl phosphates, bis(- chloroethyl)vinylphosphonate and the like while imparting some degree of permanent fire retardancy to the grafted substrate requires substantial additions of polymer onto the fiber (add-on) for effective fire retardancy which unfortunately adversely afiects the abrasion resistance of the grafted substrate. Highly halogenated polymers are particularly detrimental to abrasion resistance due to the hydrolytic effect upon the cellulose of the relatively labile halogen atom while a multi-functional vinyl molecule tends to embrittle, thus weakening the grafted fabric.

The addition of resinous materials to fabrics to impart a permanent press character to the fabric is known to drastically reduce the abrasion resistance of a cellulosic fabric and as a result, the use of cotton-polyester blend fabrics or other cellulosic-synthetic fiber blends have become popular for such pennanent press treatments in an attempt to compensate for the loss in abrasion resistance and strength incurred by the resin treatment on the cellulosic fiber.

Conventional durable press resins in current use do not impart any significant fire retardancy to the cellulosic substrate. Cellulosic textiles are very flammable especially when in a napped or brushed form. Many treatments, in addition to graft copolymerization dis cussed above, have been devised for adding flame retardant characteristics to cellulosic textiles with varying degrees of permanency. Chemicals rich in phosphorous and nitrogen have been devised which when padded onto the cellulosic substrate and subsequently cured with heat imparts a flame retardant property with some degree of permanence (durable). Flame retardancy achieved by this technique usually is durable to a number of home launderin gs but the fabric so treated suffers from a loss of hand, and a reduction in abrasion resistance and strength through a stiffing of the textile structure.

The monomers, diethylphosphatoethylmethacrylate and diethylphosphatoethylacrylate, have been disclosed in Canadian Patent No. 736,508 issued June 14, I966 entitled "Dialkyl Phosphatoalkyl Acrylates and Methacrylates and Processes for Preparing Same. At page 18 of the British patent there is disclosed the use of such compounds for imparting exceptionally good flame-retardant properties to textile and like materials such as leather when the latter are impregnated there- 2 with. This Canadian patent does not suggest a graft copolymerization of the compounds onto cellulosic fabrics nor the significant improvement in abrasion resistance discovered and disclosed herein.

SUMMARY OF THE INVENTION polymerized fabric provided also has outstanding fire retardancy.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The graft copolymerization of cellulosic materials (fbers or fabrics) with vinyl compounds is well known in the art. The graft copolymerization of cellulosic substrates with diethylphosphatoethylmethacrylate or diethylphosphatoethylacrylate can be accomplished by any of the various methods appearing in the literature for graft copolymerizing. Examples of suitable graft copolymerizing processes for making the fabrics and fibers of the present invention are disclosed in U.S. Pat. No. 3,359,224, entitled Thioated Cellulosic Amylaceous Substrates-Ethylenically Unsaturated Monomer Graft Copolymer, issued to R. W. Faessinger et al.; U.S. Pat. No. 2,955,015, entitled Graft Copolymerization of Certain Esters of Acrylic Acids With Cellular Substrate issued to N. Segrow et al.; and U.S. Pat. No. 3,083,118, entitled Method Of Depositing A Polymer of Olefinically Unsaturated Monomer Within A Polymeric Material And The Resulting Product", issued to D. .l. Bridgeford, which disclosures are incorporated herein by reference with respect to teaching methods for graft copolymerization. Many other publications demonstrate various in situ addition of polymers by pad-on-and-cure techniques initiated by heat or high energy irradiation and are well known to those skilled in the art.

Typical cellulosic fabrics are cotton, rayon and linen fabrics. The tenn fabric" as used herein includes substrates in a woven, nonwoven, molded or knitted form since the shape and structural characteristics of the fabric are not significant. The cellulosic fabric may be a blend of cellulosic fibers with non-cellulosic fibers such as synthetic fibers (e.g., nylon and polyester) provided the cellulosic fiber constitutes at least about 50% of the fibers by weight. The term "cellulosic fiber" is used herein for its common meaning and includes both regenerated cellulosic fibers such as rayon and natural cellulosic fibers such as cotton fibers and fibers obtained from other plants.

By durable (permanent) press resin is meant any of the innumerable resin systems composed of nitrogencontaining compounds such as trimethylolmelamine, hexamethoxymethylmelamine, dimethyloldihydroxyethylene urea, variously substituted dimethyl triazones, bismethoxymethyl urea and the like which are readily available to textile finishers under a variety of trade names. The present invention does not include the discovery of durable (permanent) press resins but comprises in part the discovery of the compatability of such resins with the abrasion resistant fibers and fabrics disclosed herein. No special precautions are needed in the application of these durable press resins on the graft copolymerized fabrics of this invention and the resin manufacturers directions for use are to be fol lowed. The amount of resin required will be dictated by the degree of durable press required in the finished fabric and the instructions of the manufacturer. Such resins can be added onto the grafted fabric and are usually employed in percentages of from about 0.5% to about 15%.

Monomers suitable for use in the present invention are l. diethylphosphatoethylacrylate, which has the following formula:

and, 2. diethylphosphatoethyl methacrylate, which has the following formula:

In addition to increasing the abrasion resistance of cellulosic fabrics, the monomers also impart durable flame retardancy to the fabric. The flame retardancy is more durable than the flame retardancy obtained when cellulosic fabrics are impregnated with the monomers rather than graft copolymerized with the monomers.

The amount of the monomer, diethylphosphatoethylmethacrylate, or diethylphosphatoethylacrylate, to be used will vary depending on the degree of abrasion resistance and/or the degree of fire retardancy desired. The grafted cellulosic substrate preferably contains enough polymer, poly(diethylphosphatoethylmethacrylate) and/r poly(diethylphosphatoethylacrylate) to yield a phosphorus content of from about 0.5 to by weight of the graft copolymerized fabric based upon the weight of cellulosic fibers in the fabric. However, the more preferred range is from about 1.5 to 3.5% by weight phosphorus on the fabric, with the lower value preferred when durable press resins are to be used and the upper value when used alone on an all cellulosic substrate.

Diethylphosphatoethylmethacrylate is the preferred monomer because of its greater stability and higher grafting efi'iciency.

ln order to describe the present invention so that it may be more clearly understood, the following examples are set forth. These examples are set forth primarily for the purposes of illustration, and any specific enumeration of detail contained therein should not be interpreted as a limitation of the broad concept of this invention. All proportions given herein are by weight unless indicated otherwise.

EXAM PLE l Four specimens (l, 2, 3 and 4) of cotton flannelette having a basis weight of 3% al./yd. were graft copolymerized with diethylphosphatoethylmethacrylate to various polymer add-ons onto the fabric by the method of Faessinger et al. described in US. Pat. No. 3,359,224. One grafted specimen (4) and an ungrafted control (A) were given an after-treatment with American Cyanamids Aerotex M-3 (trimethylolmelamine) to impart durable press character to the fabric. All specimens, including one untreated control (B), were subjected to a single standard home laundering and to the Tabor Abrasion Test (l-l-l8 abrasion wheels) and the number of cycles to failure was noted. The percentage of polymer and/or resin addition to the specimens and the abrasion test results are given in Table 1.

EXAMPLE [I Two specimens (5 and 6) of cotton flannelette fabric having a basis weight of 3% oz./yd. were graft copolymerized with diethylphosphatoethylmethacrylate to about 12% polymer content by the method of Segrow, ct al, described in US. Pat. No. 2,955,015. One grafted specimen (6) and an ungrafted control (C) were given an after-treatment with Aerotex M-3 (American Cyanamid, trimethylolmelamine) to impart durable press character to the fabric. The specimens and one untreated, ungrafted control specimen (D), were laundered and then subjected to the Tabor Abrasion (H-l 8 abrasion wheels) test and the number of cycles to failure was noted. The percentage of polymer and/or resin addition and the results are given in Table 1.

EXAMPLE III Two specimens (7 and 8) of cotton flannelette having a basis weight of 3% oz./yd. were graft copolymerized with diethylphosphatoethylmethacrylate to various polymer add-ons by the method of Bridgeford described in US. Pat. 3,083,118. One grafted specimen (8) and an ungrafted control specimen (E) were given an aftertreatment with Aerotex M-3 (American Cyanamid, triethanolmelamine) to impart durable press character to the fabric. The specimens, and one untreated, ungrafted control specimen (F), were subjected to the. Tabor Abrasion test (H4 8 abrasion wheel) after a single home-type laundering, and the number of cycles to failure was noted. The percentage of polymer and/or resin addition and the results are given in Table I.

EXAMPLE IV Two specimens of rayon challis fabric (9 and 10), having a basis weight of 4 oz./yd. were grafted by first padding on a sufficient quantity of a bath composed of an emulsion consisting of cliethylphosphatoethylmethacrylate and a catalytic amount of potassium persulfate, to yield a grafted polymer add-on of about 17.5%; then drying and curing the specimens in an oven at 250F. for about 15 minutes. After a post-polymerization wash in sodium bisulfite solution followed with fresh water rinse, one grafted specimen (l0) and an ungrafted specimen (G) were given an after-treatment with Aerotex M-3 (American Cyanamid, trimethylolmelamine) to impart durable press character to the treated fabric. The specimens, and one untreated ungrafted control specimen (H), were subjected to the Tabor Abrasion test (l-l-l8 abrasion wheels) and the number of cycles to failure noted. The percentage of polymer and/or resin addition and the results are given in Table I.

EXAMPLE V Several specimens (11 and 12) of cotton/polyester blend (65 35) fabric having a basis weight of 4 oz./yd.

EXAMPLE Vl Two specimens, (13 and 14) of cotton flannelette having a basis weight of 3% oz./yd. were graft copolymerized with diethylphosphatoethylmethacrylate as described in Example I. Specimen l4 and control specimen (M) were after-treated with Aerotex P-225 resin (American Cyanamid, hexamethoxymethylmelamine) in the manufacturers prescribed manner. Portions of the specimens and one untreated, ungrafted control specimen (N) were subjected to the Tabor Abrasion test (l-l-l8 abrasion wheel) after a single homestyle laundering and the number of cycles to failure was noted. The percentage of polymer and/or resin addition and the results are reported in Table I.

EXAMPLE Vlll Portions of the specimens of Example Vll after the single homestyle laundering were tested for flame retardancy according to the U.S. Department of Commerce procedure DOC FF 3-71. Control specimens M and N burned their entire length while specimen l5 self-extinguished after 2.2 seconds with a char length of 3.6 inches.

TABLE 1 Example No. Specimen No. Percent Resin Polymer Add-n Fail Cycles 1 1 19.1 78.2 I Z 24.3 78.4 I 3 33.1 94.8 i 4 7.3 19.1 77.4 I A 5.7 42.5 1 8 Control 76 II 5 12 1 19 ll 6 7.1 12 86 II C 7.3 69 II D Control 96 Ill 7 21 191 Ill 8 21 74 III E 7.3 69 III F Control 96 IV 9 7.5 69 IV 10 5.8 7.5 53 IV 6 7.5 43 [V H Control 66 V l l 27 73 V 12 5.0 27 71 V l 6.0 53 V J Control 65 VII 8.2 24.5 66 VII M 4.0 30 VII N Control lOl men (K) were after-treated with Permafresh 183 resin (Sun Chemical Company, dimethyloldihydroxyethylene urea) in the manufacturer's prescribed manner. The treated specimens and an untreated control specimen (L) were repeatedly laundered and the laundering abrasion resistance as measured by the loss in weight was observed after 1 and 50 launderings. The loss in dry fill breaking stress of each specimen was observed.

EXAMPLE VI] A specimen (15) of cotton flannelette having a basis weight of 3% ozJyd. were graft copolymerized with diethylphosphatoethylmethacrylate as described in Example l. Specimen l5 and an ungrafted control speci- What is claimed is:

l. A cellulosic fabric having improved abrasion resistance comprising a cellulosic fabric graft copolymerized with a monomer selected from the group consisting of ethylphosphatoethylmethacrylate and ethylphosphatoethylacrylate.

2. The cellulosic fabric of claim 1 having an amount of monomer graft copolymerized onto the cellulosic fabric to result in a phosphorous content of from 0.5% to 10% based upon the weight of cellulose fibers in the fabric.

3. The abrasion resistant fabric of claim 1 in which the cellulosic fabric is a blend of cellulosic fibers with non-cellulosic fibers in which the cellulosic fibers comprise at least about 50% of the fibers in the fabric.

4. The abrasion resistant cellulosic fabric of claim 1 further comprising a durable press resin added onto the cellulosic fabric after graft copolymerization.

5. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a cotton containing fabric.

6. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a rayon containing fabric.

7. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a non-woven fabric.

8. The abrasion resistant fabric of claim 1 in which the fabric is a knitted fabric.

1 i I i i 

1. A CELLULOSIIC FABRIC HAVING IMPROVED ABBRASION RESISTANCE COMPRISING A CELLUOSIC FABRIC GRAFT COPOLYMERIZED WITH A MONOMER SELECTED FROM THE GROUP CONSISTING OF ETHYLPHOSPHATOETHYLMETHACRYLATE AND ETHYLPHOSPHATOETHYLACRYLATE.
 2. The cellulosic fabric of claim 1 having an amount of monomer graft copolymerized onto the cellulosic fabric to result in a phosphorous content of from 0.5% to 10% based upon the weight of cellulose fibers in the fabric.
 3. The abrasion resistant fabric of claim 1 in which the cellulosic fabric is a blend of cellulosic fibers with non-cellulosic fibers in which the cellulosic fibers comprise at least about 50% of the fibers in the fabric.
 4. The abrasion resistant cellulosic fabric of claim 1 further comprising a durable press resin added onto the cellulosic fabric after graft copolymerization.
 5. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a cotton containing fabric.
 6. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a rayon containing fabric.
 7. The abrasion resistant cellulosic fabric of claim 1 in which the fabric is a non-woven fabric.
 8. The abrasion resistant fabric of claim 1 in which the fabric is a knitted fabric. 